The Leader of Opposition in the Rajya Sabha and Congress MP Ghulam Nabi Azad said, “This man (Subramanian Swamy) doesn't understand the difference between words used in streets and ones used in Parliament.”

On Wednesday, Swamy – on his first day in the Upper House – had caused an uproar by naming Congress president Sonia Gandhi while speaking on the AgustaWestland VVIP chopper scam issue.